Die holder



Oct. 3, 1939' E. s. CORNELL, 'JR

DIE HoLDER Filed Jan. 22, 1936 4 Sheets sheet l l woog@ C 5| DIE HOLDER Filed Jan. 22,-1956 4 .Sheets-sheet 2 INVENTOR Edw d 5 CrnelLJr:

HIS ORNEY Oct. 3, 1939.

E. s. CORNELL'. JR

DIE HoLDE Filed Jan. 22, 1936 4 Sheets-Sheet 3 NCNM MS.. T mdwvm En.v

Oct. 3, 1939.

E. S. CORNELL. JR

DIE HOLDER Filed Jan. 22, 1936 4 Sheets-Sheet 4 Ti- 35 i INVENTOR Edward 5. mel |,Jrt

' H15 A NE Patented ct. 3, 1939v PATENT oFFicE 2,174,970 DIE HOLDER Edward S. Cornell, Jr., Larchmont, N. Y., assigner, by' mesne assignments, to American Radiator &

Standard Sanitary Corporation,

New York,

N. Y., a corporation of Delaware 'Application January 22, 1936, Serial No. 60,171

18 Claims.

My present invention relates to punching and forming machinery and more particularly to an improved resiliently mounted die holder.

In the cold working of metal and particularly in the cold working of non-ferrous metal such as copper or similar metal, wherein the material being worked upon vis held in a die, and punches are used to cause a cold flow of the metal for the purpose of forming the same to the shape of l0 the cavity'in the die, there isa'tendency for the punch or punches to adhere to the material being worked upon. Under such circumstances considerable force is required to free the punch or punches from the material being worked upon,

and when once freed it has heretofore been impossible to control the force being applied to free the`punch,'with the result that the die holder,

' or the punches, or both, may be brought to a sudden stop against each other or against adjacent parts of the punch press in which the same are located, and such sudden stop has heretofore been the cause of serious damage to, or total destruction of, expensive punches, dies, or die holders, or even the punchpress itself In my present invention I have sought to devise a die holder, and particularly a mounting therefor, which would. obviate the objections to prior devices of this kind as above pointed out. To this end, I have devised a resiliently mounted 30 die holder or analogous device which, Whilev it may not decrease the tendency of the punch or punches to adhere or stick to the material being worked upon, will nevertheless take up the shocks incident to the sudden release of the punch or punches, and thereby obviate the liability of damage to, or spoilage of, either the dies, the die holder, punch orl punches, or the punch press in whichthe same are mounted.

In carrying out my invention lI preferably slidthat, as the punches move into position to perform their operation, the wedges or similar elements for maintaining the die elements in close relation to eachother, are yieldingly forced into wedging position, and such resilient mounting takes up the shocks incident to the release of ably mount the die holder in slideways forming ""oi Fig. 3, and

vthe xed punch from the material being worked lupon. l

My preferred die holder is therefore completely resiliently mounted and is movable by the movable punch into operative position by yielding 5 'pressure applied by the plunger of the. punch press through the resilient mounting, such movement forcing the resiliently mounted die holder into position against a iixed part of the die holder and into working association with the stationary l0 punch. v

A feature of my invention therefore, is a resilient mounting for a die holder.

A feature of my invention is a die holder in which the die is moved under yielding pressure against a fixed stop during the operative movement of the punches or other tools.

A feature of my invention is a resiliently mounted die holder cooperating with a xed and a movable punch, and in which the movable punch forces the die holder into association with the iixed punch under yielding pressure.

A feature of my invention is a resiliently mounted die holder in which the die elements held therein are yieldingly forced into close association with each other during the operative stroke of the punches associated therewith.

A feature of my invention is the provision of wedgesfor mdving theV die elements into operative relation to each other. 30

A feature of my invention is the provision of wedges for forcing and maintaining the die elements in operative relation to each other. A feature of my invention is the provision of means for forcing the die elements into operative relation to each other with a force proportional to the force exerted on the material in the die elements while being worked upon.

vIn the accompanying drawings,

Fig. 1 is a front elevation of my improved die holder mounting, having associated therewith so much of the punch press asis necessary to illustrate the practical working thereof;

Fig. 2 is a side elevation of the structure shown in 1; 45

Fig. 3`is a section on the line 3 3 of Fig. 2, looking in the direction of the arrowsshown in Fig. 2, and showing the resiliently mounted die holder in its uppermost or non-operative position, or an enlarged scale;

f! Fig. 4 is a view similar to Fig. 3, but showing 'the resiliently mounted die holder in its lowermost, or operated position;

Fig. 5 is a sectional detail view on the line 5 5 Fig. 6 is a section on th/line 6-6 of Fig. 5. Referring to the drawings, IIJ designates a die bolster, which ordinarily forms an integral part v of the die holder mounting, on the top face of which bolster I8 `'are secured, by bolts II, a front slide I2 and a rear bracket I3. The front slide I2 and rear bracket are securely held in position A relative to each other. The front slide I2 and the rear bracket I3 are cut awayv to provide a space therebetween. Referring to Fig. 1, the faces'of such cutaway portions are shown as forming vertical slide faces designated by the reference numeral' I1. Such faces are also i1- lustrated and designated in Fig. 3 and between such faces is slidably mounted the resiliently mounted die holder forming an element of my present invention.

The die holder is comprised essentially of a lower bridge member I8 and a top bridge member I9, secured together by means of a plurality of bolts 20, outer wedge blocks 2l being interposed between the indicated respective planar recessed portions of the bottom bridge I8 andthe top bridge I9 to space the same apart. 'I'he assembly of the lower bridge, top bridge and outer wedges is movable vertically in the yslideway formed by the front slide I2 and the rear bracket .I3,.the upper movement being limited in a manner to be hereinafter described,l and the lower` movement being limited by the engagement of the lower bridge I8 die bolster I0.

The lower bridge I8 is provided with a central vertically arranged perforation 22, through which may pass the bottom punch holding screw 23, the .bottom punch holding base 24 and the bottom punch 25. 'IIhe bottom punch holding screw 23 `seats in a depression in theupper face of the die bolster III,` and is secured in position by the bottom punch holding screw 26. In such arrangement the bottom punch 25 is stationary and immovable, being xed to an integral part of the punch table (not shown).

`The top -bridge I9 is'provided with a central vertically arranged perforation 21, through which may'pass the cap 28 for the upper punch, and

also the upper punch 29. The upper punch 29 is secured by the cap 28 to the upper punch holding screw 30, and this punchholding screw 30 is --cesses yin the punch housing 32.

screwed into the punch stem 3|. The-punch stem 3I is screwed into the punch housing 32, which is o1' the nature of a cross-head, which, together with the punch stem 3|, is secured to the ram of the punch press. The punch stem is provided with a main adjusting nut 33 and a main adjusting lock nut 34, these two nuts being employedto determine the position of the upper punch 29 with respect to the length of travel ofl the same through, the perforation 21 in the top bridge I9.

On the top -of the top bridge It on each side thereof are a plurality of'spring studs 35 which are designed to hold'.A in position the lower ends ofcoil springs 36. The upper vends of these coil springs 36 set in depressions or rel The punch housing 32 is also provided, adjacent to either nd thereof, with threaded. perforations into w/ith the upper'face of the' which screw the upper ends of stripper rods 31. These stripper rods 31 are provided with noncircular portions 38 arranged at various points along their lengths between the punch housing 32 and the top bridge I9, for the reception of a wrench with which to rotate and adjust the same in the threaded perforations in the punch housing 32.

The top bridge I9 and the lower bridge I8 are provided with aligned perforatlons, in alignment with the stripper rods 31, and in which aligned perforations and stripper rods 31 slidably pass, as clearly shown in Fig. 3. I'he lower portion of each perforation through the lower bridge I8 is formedwith an enlarged counterbored portion 38, in which slides the head- .39 of the stripper rods 31. Such counterbored portions 38 limit the upward movement of the stripper rods 31, and

therewith pre1-establish a relationship between the top bridge'lI9 and the punch housing 32. After the stripper rods 31 have been ,adjusted to determine the proper relationship of the punch housing 32 and top bridge I9 they are fixed in position by means of set screws 40, as clearl -shown in Fig. 1. I

Screwed to the lower face of the die bolster .I0, and symmetrically arranged with respect to each other, and to the bottom-punch holding screw 26, are spring studs 4I. 4I are arranged in pairs, as shown in the drawings and the lower ends of such studs are threaded as indicated by the reference numeral 42 to receive sets of adjusting and lock nuts 43 and 44 respectively. Each pair of studs 4I has associated therewith and freely slidable thereon, a washer plate 45 on which seat the lower end of coil springs 46. The washer plates 45 thus act The spring studs as a xed stop for the coil springs 46. Each pair of spring studs 4I also has slidably mounted than the spring pressure stud 48. The die bolster Ill and the lower bridge I8 are provided with l"'perforations in alignment with each other and in which perforations are sildably mounted the stated cylindrical members 49.

When the spring pressure studs 48 are in engagement with the lower face of the ,die bolster I0, and the lower bridge I8 is in its uppermost position as shown for example in Fig. 3 the upper end of the members 49 lie below the surface of the stated planar recessof the upper face of the lower bridge I8.

Theupper end of each of the cylindrical members 49 is drilled and tapped to lreceive the lower cylindrical portion 50 and the threaded portion 5I of a wedge releasing rod 52. The wedge-releasing rods 52 are provided 'with an enlarged cylindrical portion 53 at their upper ends. and such enlarged portions are slidably mounted in perforations provided in the top bridge I9. Ihe

upper ends ofthe enlarged portions 53 are provided with non-circular portions 54 by means of which the wedge releasing rods 52 may be rotated A to alter their position relative to the cylindrical springs 51. The lower ends of such coil springs 61 engage with the .bottom of the recess in the Y upper face of the lower bridge I8. Such springs urge the inner wedges 56 into engagement with the under side of thel heads 53 of the stripper rods 52, when the die holder is at raised, i. e., its Fig. 3 position.

Referring to Fig. 6 it will be noted that a portion of the lower` surface of the inner wedges 56 is cut away, as indicated by the reference numeral 51a, and such cut away portion 51a provides a bevel 58 which cooperates witha corresponding bevel portion formed on a hardened steel plate 59 keyed into the recess in the lower bridge I8, and secured rigidly to such bridge by screws 60. This latter construction is provided for the purpose of accurately positioning the inner wedges 56 when the parts of the device are in their uppermost position and the die members 6I, (i2- as later described-have been removed from their position between the'top bridge I9 and the lower bridge i8.

The assembly of coil springs 46, spring pressure studs 48, and the wedge release rods 52, forms a means for actuating the inner wedges 56 into operative position under a yielding pressure. Such pressure is commensurate with the strength of the springs I6, and the length of travel .of the die carrying members above described. Also such springs I6 act to release,\without shock, the inner wedges 56 from their elective compression exert- Aing position with respect to the die members, to

be hereinafter referred to, and take a position which will permit the removal and replacement of the die memberswith respect to the carrying.

devices therefor.

The space between the inner wedges 56 is amply wide to allow the insertion of cooperating die members 6I and 62.' Such die members may have in their cooperating faces any form of lcavity desired, the cavity-tc be. fabricated in accordance with the shape it is desired to give to the material to be worked. upon. Also in such die members 6i and 62, and communicating with the cavity therein, are passages 63 and 655 communicating with the cavity aforesaid and in alignment witheach other, and also in alignment with the top and bottom punches respectively.

On the front slide I2 is formed a bracket 65, the upper face 65a of which is substantially on the same level as the surface of the recess formed in the lower bridge Iii when such lower bridgefrom a lug 68 in which is secured.v by nut 68 one endof a shaft 10, and which shaft has its free end slidably mounted in a suitable bearing pro- .association with the die member 6I.

vided on the front slide I2. ,On the shaft 1l is lformed a rack 1I, which engages with and is' driven. by a pinion 12 secured to a shaft 13 rotatably mounted on the front slide I2. Secured to the end of the shaft 13 is a hand wheel 14, by means of which the shaft 13, and therefore the pinion 12, may be rotated either clockwise or counter-clockwise.

Such rotary movement of the hand wheel 13 will impart to shaft 10 movement to the right or left, and therefore will impart a similar movement to the slide 61 parallel to the upper surface of the bracket 65.

Formed on the bracket 65 is a' vertical member 15, the inner vertical face of which is always in substantial alignment with the left hand inner face `of the inner wedge 56. Secured to the top race of the member 15 is a plate 16, having at its inner end a depending top runner. 11. This top runner 11 is in alignment with a. bottom runner 18 which is inset into the upper face of the bracket 61. The upper and lower runners cooperate respectively with grooves 19 and 80 in the die member 6 I.

Secured to the slide 61 in an upwardly extending bracket 8|, the inner face of which is parallel to the opposing face of the member 15, and when the Vslide 61 is in the position shown in Fig. 1, is in substantial alignment with the inner face of the righthand wedge 56, shown in Fig. 3. Secured to the top of the bracket 8| is a plate 82 provided with a. downwardly depending top vrunner 83 which is in alignment with a bottom move the bracket 8l to the right, as shown in Fig. 1 thus separating the die members 6I and 62 from each other, While thus positioned the cavity formed in such die members collectively is separated into two parts, and therefore it is relatively easy for Yan operator to position a mass of material, such as the mass of material 88, in for example, that portion of the cavity formed in the die member 6I. The hand wheel 15 is again rotated, this time to move the bracket 8l toward the member 15 and bring the die member 62 into positioned the die members 6! and 62, as a unit, and guided by the stated top and bottom runners may be pushed off the bracket 65 and slide 61 lower bridge I8, and between the inner wedges 56. When thus in position and with the mass of metal 88 in the cavity formed in such die members 6I and 62 the apparatus is in condition for' operation.

' Assuming' the conditions stated above, that is, that the parts oi the device are in the position shown in Figs. i, 2 and 3, with the die members 6I and 62 in cooperative relation withthe top bridge and lower bridge, and with the inner Wedges 56, and with the passages 63 and 64 in 'such die members in alignment with the top When thus Ainto position between the top bridge i9 and the punch 29 and the bottom punch 25 respeetively,

the followingoperations may take place., The operator manipulates the lever (not shown) of the press to cause a downward-'move- Y of material 88 will be caused to flow into and ment of the ram of the punch press (not shown).

whereupon the punch housing '32 carrying the top punch 29 and the stripper rods 31 is moved 1 downwardly from the position shown in Figs.-1,

2 and '3 toward the position shown in Fig. 4. The die holder assembly, comprising the top bridge I9, lower bridge I8, the outer and inner wedges and the die members 6I and 62 may or may Inot move downwardly at this time. lHowever, as the punch housing 32 continues its downward movement the upper coil springs 36 will be compressed and a downward movement of the above assembly will take place. Such downward movement of the assembly will continue until the top of the lower punch engages with the mass of material 88. i

Also, and possibly at this time, the upper punch '29 will have moved into engagement with the v mass of -material 88.

Duringv such downward movement of the assembly the stripper rods 31 will move relative to the top bridge I9 and the lower bridge I8 and the heads 39 thereof will move into the passages 38a in the bolster I6 as shownv in Fig.l 4. Also, during this downward movement the lower end of the inner wedges 56 will move into engagement with the upper end of the cylindricalvmembers 49 formed integral with and at the top of the spring pressure studs 48. This will result in a downward movement of the spring pressure studs 48, and a. simultaneous downward movement of the spring pressure stud bases 4I, with a consequent compression of the coil springs 46. Under these conditions there will be a resilient pressure exerted on the inner Wedges 56 in an upward direction, and because of the construction of the adjacent faces of the inner wedges 56, and the outer wedges 2|, there will be a lateral movement of each inner wedge 56 toward it's associated die member, and a resultant compressive action on the die members 6I and 62 in a direction toward each other. The cavity formed in such two members will be completely closed preventing escape of the mass of material 88 when the same is acted upon by the upper and lower punches respectively.

As the downward movement of the punch housing 32 continues, the punches 29 and 25 will gradually assume the position relative to each other asshown in Fig. 4, and duringsuch movement' into such position the material of the mass iill the cavity in the die members 6I and 82 inv which the material is located. The downward movement of the die holder assembly is terminated when the lower bridge I8 moves into engagement with" the upper surface of the die bolster I and the downward movement of the punch 29 with respect to the die members 6I and 62 is-terminated when the main adjusting lock nut 34 on the punch stem 3l engages with the upper surface of the top bridge I9.

It has been found that the punches 29 and 25 will frequently stick in the material I8 being worked upon, and that considerable force is necessary to withdraw such punches from the material. Also it has been found that more frequently the top punch 29 is the first 'of the punches to be released from such material, and l therefore means must be used to afterwards release the lower punch 25 from such material. Heretofore when the upper punch 29 was released, force was being exerted on such punch. 2.9, and-upon the sudden release of such upper punch from the material 89 the entire upper punch carrying means would be brought to a and arrangement of parts comprising my imsudden stop against some portion of the punch press with consequent serious .damage to the equipment.

In my present invention all such damage is obviated, as when the upper punch 29 is released l from the material 88 there will 'be no sudden upward surge of the upper punch 29 and carrying parts therefor, as the springs 36 maintain the die holder assembly initially in engagement with the upper surface of the die bolster I6.

'I'he punch housing 32, therefore, and all parts carried thereby, including the stripper rods 31 will move upwardly at aconstant speed until the heads 39 of the stripper bolts 31 engage in the rtop of the counterboard portion 38 of the passages in the lower bridge I8, and the assembly above referred to willbe forcibly and steadily moved upwardly. Such upward movement is assisted by the springs 46, whichtend to move the spring pressure studs 48"and therefore the cylindrical members 49 attached thereto, upwardly from the position shown in'lFig. 4 to the position shown in Fig. 3.

The upward movement of the assembly referred to will cause a freeing of the lower punch 25 `from the material 88, and when this happens the upward movement of such assembly is accelerated because of the action of the coil springs 46. No

shock will result because of such sudden movement of the stated assembly. as the shock to which the same might be subjected is rabsorbed by the still substantially compressed springs 36. Assuming the stated assembly .to have been moved upward to approximately itsFig. 3 position, it is apparentthat th'e enlarged cylindrical Vportion 53 on the wedge. releasing rods 52 will come into sudden engagement with the-upper surface of the'inner wedges 56, with the result that such wedges will be moved downwardly into their Fig. 3 position, in which position'removal of the die members 6I, 62 from the die holder is permitted. Springs 51 cushion the impact of the heads 53 while maintaining the die members 6I, 62 in suitable work-securing position.

'I'he accompanying drawings and description illustrate `and describe respectively one embodiment of my improved invention. While I have shown such embodiment somewhat in detail, it is to be understood that I may vary the size, shape proved device within relatively wide limits without departing from the spirit of the invention.

- I claim:

1. In an improved mounting for a die holder, the combination of a die holder, mutually separable diemembers positioned therein, mutuallyl displaceable wedges arranged to be disposed upon opposite sides of said mutually separable die members, and reciprocable means for jointly operating said die holder and said wedges to effect wedging relation of said wedges relative to said mutually separable die members in a movement of said reciprocable operating means and nonwedging relation of said wedges relative to said mutually separable die members in an opposite movement of said reciprocable operating means.

2. In an improved mounting for a die holder, the combination of a base, a die holder. mutually separable die members positioned in the die holder, mutually displaceable wedging means cooperating with the die members and the dfe holder, andarranged to be disposed upon /opposite sides of said mutually separable die r emcarrying bers, and reciprocable means resiliently said mutually displaceable wedging means and jointly operating said die holder and said mutually -displaceable wedging means.

3. In an improved mounting for a die holder, the combination .of a base, guide-ways thereon,

, a die holder mounted on the guide-ways, mutually separable. die members positioned in the die holder, reciprocable means for resiliently supporting the die holder in position on the guideways, mutually displaceable wedging means cooperating with the die members and the vdie holder, and resilientmeans supported by said reciprocable die carrier supporting means for yieldingly moving the wedging means into operative relation with respect to said mutually separable die members in a movemen-t of said reciprocable supporting means and into non-operativev relation of said wedge means in respect to said mutually separable die members in an opposite movement of said reciprocable supporting means.

4.In an improved mounting for a die holder, the combination of .a base, a' die holder mounted for reciprocating movement toward and from the base, mutually separable die elements housed within the die holder, mutually displaceable wedging means carried byusaid die holder and associated with said mutually separable die members, and reciprocable means operative upon the movement of said die holder for moving said wedging means into wedging relation with respect to said mutually separable die elements `upon movement of said die holder toward the base and for moving said wedging means into means upon movement of the die holder toward the base to move said wedging means into .wedging position with respect to said die members.

6. In an improved mounting for a die holder,

the combination -with a base, of guide-ways mounted thereon, a die holder mounted for reciprocating movement'on the guideways toward and from the base, die members housed within the die holder, wedging means in said die holder associated with the die members, and means mounted in the base for moving said wedges into association with the die members whereby to move said die members into close association with each other.

7. In an improved mounting for a die holder, the combination with a base, of guide-ways mounted thereon, a die holder mounted for reciprocating movement on the guide-ways toward and from the base, a die comprising a plurality of separable members supported within said die holder, cooperating Wedges mounted within the die holder and engaging the die members for moving the same into association with each other, and means carried by the base for moving said wedges into wedging position with respect to the die members during the movement of the die holder toward the b'ase.

8. Inan improved mounting for a die holder, the combination of a base, guide-ways mounted thereon, a die holder mounted for reciprocatory motion on the guide-lways toward and from the 'ment with each other, and resiliently mounted meansv on the base engaging with the wedging means in the movement of the die holder toward the base for operating the wedging means.

9. In an improved mounting for a die holder, the 'combination of a base, guideways mounted thereon, a die holder mounted within said guideways for reciprocatory motion toward and from the base, ay punch holder movable toward and away from said die holder, means secured to said punch holder and vslidably mounted in the die holder for constraining said punch holder to move in a iixed path toward and away from said die holder, resilient means interposed between said die holder and said punch holder, a punch carried by said punch holder, and die members locate within the die holder and adapted to receive material to be worked upon, said punch holder, upon movement toward said die holder,

`causing a yielding movement of the die holder and die members carried thereby toward the base as the said punch engages with the material within the die members. e

10. In an improved mounting for a die holder, the combination of a base, a die holder yieldingly mounted for reciprocating movement toward andv from the base, die members housed Within the die holderwedging means in said die holder associated with the die members, means mounted on the base engaging with said wedging means upon movement of the die holder toward the base to move said wedging means into wedging position with respect to said die members, and

means for forcing the die members into close g association with each other during the downward movement of the die holder.

11. In an improved mounting for a die holder, the combination with a base, a die holder yieldingly mounted for reciprocating movement toward and from the base, die members housed within the die holder, wedging means in said die holder associated with the die members," means mounted on the base engaging with said wedging means upon movement of the die holder toward the base to move said wedging means into Wedging position with respect to said die members, and means for forcing the die members into association with each other with a force proportional to the force exerted by the punch on the 'material being worked upon.

the base, a punch holder movable toward andv 'away from said die holder, means secured to said punch holder and slidably mounted within the die holder for constraining said punch holder to4 move in a xed path toward and from'said die holder, resilient means interposed between said die holder and said punch holder, a punch carried by said punch holder, die members located within the die holder and adapted to receive material to be worked upon, the punch holder, upon movement toward the die holder, causing a yielding movement of the die holder and the die members carried thereby toward the base as the punch engages with the material within the die members, and means for yieldably forcing the die members into association with each other with a force proportional to the force exerted by means, punch holder. means operatively related to and on opposite sides of a die carried by said die holder, one of said 'punch holder means arranged for reciprocatory motion with respect to said die holder, means eilective for joint operation of said punch holder means with respect to work placed in the die carriedby said die holder and resilientmeans interposed between said reciprocatory punch holder means and said die holder.

14. In an improved mounting for a die holder, the combination of a die holder having a die removably contained therein, guide means for said die holder, supporting means for said guide means, resilient means for mounting said die holder with respect to said guide supporting means, punch holder means operatively related to and on opposite sides of a die mounted within said die holder, one of said punch holder meansarranged for reciprocatory motion with respect to said die holder, means eil'ectlve for joint operation oi said punch holder means with respect to work placed in the said die, and resilient means interposed between said reciprocatory punch holder means and said die holder, each of said resilient means comprising a set of resilient elements disposed in mutually symmetrical relation to one or more punches or .equivalent carried by-said punch, holder means.

15. In an improved mounting for a die holder,

*the combination of a die holder having a die" removably contained therein, guide means for said die holder, supporting means for said guide means, resilient means for mounting said die holder withinA said guide means in a manner ailordingreciprocatory movement, pimch holder means yoperatively related to and 'on opposite sides of said' die, one of said punch holder means arranged for reciprocatory motion with respect to said die holder, means eiective for joint operation of said punch holder means with respect to ways, said die holder having a die removably contained therein, punch holder means mounted for vertical reciprocatory movement with respect to said die holder means, resilient means interposed between said punch holder'and said die holder, meansi'or resiliently supporting said die holder above said base, and wedge means arranged to cooperate with said last-mentioned means during downward motion of said die holder to hold the die carried by said die holder in proper operative relationship-to said punch holder means. A

17. In an improved mounting for a die holder, the combination of a base having vertical guide- `ways mounted thereon,'a punch holder arranged for vertical reciprocatory movement with respect to said base and said guideways, a die holder slidably mounted in said guideways and arranged to dispose a die in operative alignment with respect to said punch holder, and resilient means acting in opposition on the upper and lowerfaces of said die holder for yieldably establishing a position of said die holder intermediate the said punch holder and said base.

18. In an improved mounting for a die holder, the combination with a base, of guideways mounted thereon, a die holder mounted for reciprocating movement within the guideways toward and from the base, a plurality oi' separable die members contained within the die holder, said plurality of members being in operative association to define-suitable die means, wedging means in said die` holder associated with said die members, and resilient means. mounted in said base and operatively associated with said wedging means for urging said wedges into association with said die members to move said die members into proper operative relationship.

EDWARD S. CORNELL, Jn. 

